Tear of meniscus
Encyclopedia
In sport
s and orthopedics, a tear of a meniscus is a rupturing of one or more of the fibrocartilage
strips in the knee called menisci
. When doctors and patients refer to "torn cartilage" in the knee, they actually may be referring to an injury to a meniscus at the top of one of the tibiae. Menisci can be torn during innocuous activities such as walking or squatting
. They can also be torn by traumatic
force encountered in sports or other forms of physical exertion. The traumatic action is most often a twisting movement at the knee while the leg is bent. In older adults, the meniscus can be damaged following prolonged 'wear and tear' called a degenerative
tear.
Tears can lead to pain and/or swelling of the knee joint. Especially acute injuries (typically in younger, more active patients) can lead to displaced tears which can cause mechanical symptoms such as clicking, catching, or locking during motion of the knee joint. The joint will be in pain when in use, but when there is no load, the pain goes away.
A tear of the medial meniscus can occur as part of the unhappy triad
, together with a tear of the anterior cruciate ligament
and medial collateral ligament
.
located between the tibial plateau and femoral condyles. The menisci contain 70% type I collagen. The larger semilunar medial meniscus is attached more firmly than the loosely fixed, more circular lateral meniscus. The anterior and posterior horns of both menisci are secured to the tibial plateaus. Anteriorly, the transverse ligament
connects the 2 menisci; posteriorly, the meniscofemoral ligament helps stabilize the posterior horn of the lateral meniscus to the femoral condyle. The coronary ligaments connect the peripheral meniscal rim loosely to the tibia. Although the lateral collateral ligament (LCL) passes in close proximity, the lateral meniscus has no attachment to this structure.
The joint capsule attaches to the entire periphery of each meniscus but adheres more firmly to the medial meniscus. An interruption in the attachment of the joint capsule to the lateral meniscus, forming the popliteal hiatus, allows the popliteus tendon to pass through to its femoral attachment site. Contraction by the popliteus during knee flexion pulls the lateral meniscus posteriorly, avoiding entrapment within the joint space. The medial meniscus does not have a direct muscular connection. The medial meniscus may shift a few millimeters, while the less stable lateral meniscus may move at least 1 cm.
In 1978, Shrive et al. reported that the collagen fibers of the menisci are oriented in a circumferential pattern. When a compressive force is applied in the knee joint, a tensile force is transmitted to the menisci. The femur attempts to spread the menisci anteroposteriorly in extension and mediolaterally in flexion. Shrive et al. further studied the effects of a radial cut in the peripheral rim of the menisci during loading. In joints with intact menisci, the force was applied through the menisci and articular cartilage; however, a lesion in the peripheral rim disrupted the normal mechanics of the menisci and allowed it to spread when a load was applied. The load now was distributed directly to the articular cartilage. In light of these findings, it is essential to preserve the peripheral rim during partial meniscectomy to avoid irreversible disruption of the structure's hoop tension capability.
The patient can sometimes remember a specific activity during which the injury was sustained. A tear of the meniscus commonly follows a trauma which involves rotation of the knee while it was slightly bent. These maneuvers also excite the pain after the injury; for example, getting out of a car is often reported as painful.
After noting symptoms, a physician can perform clinical tests to determine if the pain is caused by compression and impingement of a torn meniscus. The knee is examined for swelling. In meniscal tears, pressing on the joint line on the affected side typically produces tenderness. The McMurray test
involves pressing on the joint line while stressing the meniscus (using flexion
-extension
movements and varus
or valgus stress). Similar tests are the Steinmann test (with the patient sitting) and the Appley test (a grinding maneuver while the patient lies prone and the knee is bent 90°). Bending the knee (into hyperflexion if tolerable), and especially squatting, is typically a painful maneuver if the meniscus is torn. The range of motion
of the joint is often restricted.
The Cooper's sign
is present in over 92% of tears. It is a subjective symptom of pain in the affected knee when turning over in bed at night. Osteoarthritic pain is present with weightbearing, but the meniscal tear causes pain with a twisting motion of the knee as the meniscal fragment gets pinched, and the capsular attachment gets stretched causing the complaint of pain.
Also see: bounce home test, Thessally's test, Wilson test
(internal/external rotation), and Bohler's test.
• Radial tears
• Flap or Parrot-beak tears
• Peripheral, longitudinal tears
• Bucket-handle tears
• Horizontal cleavage tears
• Complex, degenerative tears
These tears can then further classified by their proximity to meniscus blood supply, namely whether they are located in the “red-red,” “red-white,” or “white-white” zones.
The functional importance of these classifications, however, is to ultimately determine whether a meniscus is REPAIRABLE. The repairability of a meniscus is dependent upon a number of factors. These include:
• Age/strength
• Activity Level
• Tear Pattern
• Chronicity of the tear
• Associated Injuries (Anterior Cruciate Ligament Injury)
• Healing Potential
and shin bone tibia
.
While the ends of the thigh bone and shin bone have a thin covering of soft hyaline cartilage, the menisci are made of fibrocartilage
tough cartilage and conform to the surfaces of the bones upon which they rest. One meniscus rests on the medial tibial plateau; this is the medial meniscus. The other meniscus rests on the lateral tibial plateau; this is the lateral meniscus.
These menisci act to distribute body weight across the knee joint. Without the menisci, the weight of the body would be unevenly applied to the bones in the legs (the femur and tibia). This uneven weight distribution would cause the development of abnormal excessive forces leading to early damage of the knee joint. The menisci also contribute to the stability of the joint.
The menisci are nourished by small blood vessels, but the menisci also have a large area in the center of that has no direct blood supply (avascular). This presents a problem when there is an injury to the meniscus as the avascular areas tend not to heal. Without the essential nutrients supplied by blood vessels, healing cannot take place.
The two most common causes of a meniscus tear are traumatic injury (often seen in athletes) and degenerative processes (seen in elderly patients who have more brittle cartilage). Meniscus tears can occur in all age groups. Traumatic tears are most common in active people from age 10-45. Traumatic meniscal tears are usually radial or vertical in the meniscus and are more likely to produce a moveable fragment that can catch in the knee and therefore require surgical treatment.
The most common mechanism of a traumatic meniscus tear occurs when the knee joint is bent and the knee is then twisted. It is not uncommon for the meniscus tear to occur along with injuries to the anterior cruciate ligament ACL
and the medial collateral ligament MCL
— these three problems occurring together are known as the "unhappy triad
," which is seen in sports such as football when the player is hit on the outside of the knee. Individuals who experience a meniscus tear usually experience pain and swelling as their primary symptoms. Another common complaint is joint locking, or the inability to completely straighten the joint. This is due to a piece of the torn cartilage preventing the normal functioning of the knee joint.
Degenerative tears are most common in people from age 40 upward. Degenerative meniscal tears are thought to occur as part of the aging process when the collagen fibers within the meniscus start to break down and lend less support to the structure of the menicus. Degenerative tears are usually horizontal in the meniscus, producing both an upper and lower segment of meniscus. These segments usually don't move out of place and therefore are less likely to produce mechanical symptoms of catching or locking.
Degenerative meniscal tears are also more common in smokers.
A torn meniscus can prevent normal pain-free motion of the knee and therefore can interfere with the patient's ability to climb stairs or get in and out of chairs and cars.
. Consequently, menisci can tear due to traumatic injury or degenerative wear (e.g., in knee joint arthritis
), and can compromise force distribution across the knee joint, increasing force concentration on the cartilage and other joint structures.
Damage to the meniscus is due to rotational forces directed to a flexed knee (as may occur with twisting sports) is the usual underlying mechanism of injury. A valgus force applied to a flexed knee with the foot planted and the femur
rotated externally can result in a lateral meniscus tear. A varus force applied to the flexed knee when the foot is planted and the femur rotated internally can result in a tear of the medial meniscus.
Tears produce rough surfaces inside the knee, which cause catching, locking, buckling, pain, or a combination of these symptoms. Abnormal loading patterns and rough surfaces inside the knee, especially when coupled with return to sports, significantly increase the risk of developing arthritis if not already present.
images (normally during weightbearing) can be obtained to rule out other conditions or to see if the patient also has osteoarthritis
. The menisci themselves cannot be visualised with plain radiographs. If the diagnosis is not clear from the history and examination, the menisci can be imaged with magnetic resonance imaging
(an MRI scan). This technique has replaced previous arthrography, which involved injecting contrast medium
into the joint space. In straightforward cases, knee arthroscopy
allows quick diagnosis and simultaneous treatment. Recent clinical data shows that MRI and clinical testing are comparable in sensitivity and specificity when looking for a meniscal tear.
or anti-inflammatory medications.
The meniscus has fewer vessels and blood flow towards the unattached, thin interior edge. In the majority of cases, the tear is far away from the meniscus' blood supply, and a repair is unlikely to heal. In these cases arthroscopic surgery allows for a partial meniscectomy, removing the torn tissue and allowing the knee to function with some of the meniscus missing. In situations where the meniscus is damaged beyond repair or partial removal, a total meniscectomy is performed. This option is avoided at all costs as total meniscectomy leads to an increased risk of osteoarthritis
(with loss of cartilage
) and eventual total knee replacement
. In some cases, a meniscus replacement is done to prevent this.
Transplants of full meniscus are accomplished successfully regularly, although it is still somewhat of a rare procedure and many questions surrounding its use remain.
Although not clinically proven some people report better recovery after a period of oral intake of glucosamine-sulphate supplement.
If the destroyed part of the meniscus was removed, patients can usually start walking using a crutch a day or two after surgery. Although each case is different, patients return to their normal activities on average after a few weeks (2 or 3). Still, completely normal walk will resume gradually and it's not unusual to take 2–3 months for the recovery to reach a level where a patient will walk totally smoothly. Many meniscectomy patients don't ever feel a 100% functional recovery, but even years after the procedure they sometimes feel tugging or tension in a part of their knee. There is little medical follow-up after meniscectomy and official medical documentation tends to ignore the imperfections and side-effects of this procedure.
If the meniscus was repaired the rehabilitation
program that follows is a lot more intensive. After the surgery a hinged knee brace is sometimes placed on the patient. This brace allows controlled movement of the knee. The patient is encouraged to walk using crutches from the first day, and most of the times can put partial weight on the knee.
The time course varies with each patient. Starting from the second month the patient maybe able to walk freely and can also do various "low-impact" exercises (static bicycle, swimming, etc.), but should expect the knee to feel stiff and sore. If the rehabilitation was done properly the patient can gradually return back to "high-impact" activities (like running). However, "heavier activities", like running, skiing, basketball etc., generally any activities where knees bear sudden changes of the direction of movement can lead to repeated injuries. When planning sport activities it makes sense to consult a physical therapist and check how much impact the sport will have on the knee.
Sport
A Sport is all forms of physical activity which, through casual or organised participation, aim to use, maintain or improve physical fitness and provide entertainment to participants. Sport may be competitive, where a winner or winners can be identified by objective means, and may require a degree...
s and orthopedics, a tear of a meniscus is a rupturing of one or more of the fibrocartilage
Fibrocartilage
White fibrocartilage consists of a mixture of white fibrous tissue and cartilaginous tissue in various proportions. It owes its flexibility and toughness to the former of these constituents, and its elasticity to the latter...
strips in the knee called menisci
Meniscus (anatomy)
In anatomy, a meniscus is a crescent-shaped fibrocartilaginous structure that, in contrast to articular disks, only partly divides a joint cavity. In humans it is present in the knee, acromioclavicular, sternoclavicular, and temporomandibular joints; in other organisms they may be present in other...
. When doctors and patients refer to "torn cartilage" in the knee, they actually may be referring to an injury to a meniscus at the top of one of the tibiae. Menisci can be torn during innocuous activities such as walking or squatting
Squatting position
Squatting is a posture where the weight of the body is on the feet but the knees are bent either fully or partially . In contrast, sitting, involves taking the weight of the body, at least in part, on the buttocks against the ground or a horizontal object such as a chair seat...
. They can also be torn by traumatic
Physical trauma
Trauma refers to "a body wound or shock produced by sudden physical injury, as from violence or accident." It can also be described as "a physical wound or injury, such as a fracture or blow." Major trauma can result in secondary complications such as circulatory shock, respiratory failure and death...
force encountered in sports or other forms of physical exertion. The traumatic action is most often a twisting movement at the knee while the leg is bent. In older adults, the meniscus can be damaged following prolonged 'wear and tear' called a degenerative
Degenerative disease
A degenerative disease, also called neurodegenerative disease, is a disease in which the function or structure of the affected tissues or organs will progressively deteriorate over time, whether due to normal bodily wear or lifestyle choices such as exercise or eating habits...
tear.
Tears can lead to pain and/or swelling of the knee joint. Especially acute injuries (typically in younger, more active patients) can lead to displaced tears which can cause mechanical symptoms such as clicking, catching, or locking during motion of the knee joint. The joint will be in pain when in use, but when there is no load, the pain goes away.
A tear of the medial meniscus can occur as part of the unhappy triad
Unhappy triad
An unhappy triad is an injury to the anterior cruciate ligament, medial collateral ligament, and the meniscus. The triad refers to a complete or partial tear of the anterior cruciate ligament, medial collateral ligament, and the meniscus...
, together with a tear of the anterior cruciate ligament
Anterior cruciate ligament
The anterior cruciate ligament is a cruciate ligament which is one of the four major ligaments of the human knee. In the quadruped stifle , based on its anatomical position, it is referred to as the cranial cruciate ligament.The ACL originates from deep within the notch of the distal femur...
and medial collateral ligament
Medial collateral ligament
The medial collateral ligament of the knee is one of the four major ligaments of the knee. It is on the medial side of the knee joint in humans and other primates. It is also known as the tibial collateral ligament, or abbreviated as the MCL.- Structure :It is a broad, flat, membranous band,...
.
Anatomy
The menisci are C-shaped wedges of fibrocartilageFibrocartilage
White fibrocartilage consists of a mixture of white fibrous tissue and cartilaginous tissue in various proportions. It owes its flexibility and toughness to the former of these constituents, and its elasticity to the latter...
located between the tibial plateau and femoral condyles. The menisci contain 70% type I collagen. The larger semilunar medial meniscus is attached more firmly than the loosely fixed, more circular lateral meniscus. The anterior and posterior horns of both menisci are secured to the tibial plateaus. Anteriorly, the transverse ligament
Ligament
In anatomy, the term ligament is used to denote any of three types of structures. Most commonly, it refers to fibrous tissue that connects bones to other bones and is also known as articular ligament, articular larua, fibrous ligament, or true ligament.Ligament can also refer to:* Peritoneal...
connects the 2 menisci; posteriorly, the meniscofemoral ligament helps stabilize the posterior horn of the lateral meniscus to the femoral condyle. The coronary ligaments connect the peripheral meniscal rim loosely to the tibia. Although the lateral collateral ligament (LCL) passes in close proximity, the lateral meniscus has no attachment to this structure.
The joint capsule attaches to the entire periphery of each meniscus but adheres more firmly to the medial meniscus. An interruption in the attachment of the joint capsule to the lateral meniscus, forming the popliteal hiatus, allows the popliteus tendon to pass through to its femoral attachment site. Contraction by the popliteus during knee flexion pulls the lateral meniscus posteriorly, avoiding entrapment within the joint space. The medial meniscus does not have a direct muscular connection. The medial meniscus may shift a few millimeters, while the less stable lateral meniscus may move at least 1 cm.
In 1978, Shrive et al. reported that the collagen fibers of the menisci are oriented in a circumferential pattern. When a compressive force is applied in the knee joint, a tensile force is transmitted to the menisci. The femur attempts to spread the menisci anteroposteriorly in extension and mediolaterally in flexion. Shrive et al. further studied the effects of a radial cut in the peripheral rim of the menisci during loading. In joints with intact menisci, the force was applied through the menisci and articular cartilage; however, a lesion in the peripheral rim disrupted the normal mechanics of the menisci and allowed it to spread when a load was applied. The load now was distributed directly to the articular cartilage. In light of these findings, it is essential to preserve the peripheral rim during partial meniscectomy to avoid irreversible disruption of the structure's hoop tension capability.
Symptoms and signs
The patient's chief complaints are usually knee pain and swelling. These are worse when the knee bears more weight (for example, when running). Another typical complaint is joint locking, when the patient is unable to fully straighten the leg. This can be accompanied by a clicking feeling. Sometimes, a meniscal tear also causes a sensation that the knee gives way.The patient can sometimes remember a specific activity during which the injury was sustained. A tear of the meniscus commonly follows a trauma which involves rotation of the knee while it was slightly bent. These maneuvers also excite the pain after the injury; for example, getting out of a car is often reported as painful.
After noting symptoms, a physician can perform clinical tests to determine if the pain is caused by compression and impingement of a torn meniscus. The knee is examined for swelling. In meniscal tears, pressing on the joint line on the affected side typically produces tenderness. The McMurray test
McMurray test
The McMurray test, also known as the McMurray circumduction test is used to evaluate individuals for tears in the meniscus of the knee. It is a rotation test for demonstrating torn cartilage of the knee...
involves pressing on the joint line while stressing the meniscus (using flexion
Flexion
In anatomy, flexion is a position that is made possible by the joint angle decreasing. The skeletal and muscular systems work together to move the joint into a "flexed" position. For example the elbow is flexed when the hand is brought closer to the shoulder...
-extension
Extension (kinesiology)
In kinesiology, extension is a movement of a joint that results in increased angle between two bones or body surfaces at a joint. Extension usually results in straightening of the bones or body surfaces involved. For example, extension is produced by extending the flexed elbow. Straightening of...
movements and varus
Varus
-People:*Publius Attius Varus , Roman governor of Africa.*Publius Quinctilius Varus , politician of the Roman Empire.*Quinctilius Varus -People:*Publius Attius Varus (died 17 March 45 BCE), Roman governor of Africa.*Publius Quinctilius Varus (46 BCE - 9 CE), politician of the Roman...
or valgus stress). Similar tests are the Steinmann test (with the patient sitting) and the Appley test (a grinding maneuver while the patient lies prone and the knee is bent 90°). Bending the knee (into hyperflexion if tolerable), and especially squatting, is typically a painful maneuver if the meniscus is torn. The range of motion
Range of motion
Range of motion , is the distance that a movable object may normally travel while properly attached to another object. It is also called range of travel, particularly when talking about mechanical devices and in mechanical engineering fields...
of the joint is often restricted.
The Cooper's sign
Cooper's Sign
Cooper's sign is a test for meniscal damage in the knee. It involves the patient complaining of joint line pain in the affected knee when turning over in bed at night changing position of their legs. It is thought that the meniscal tear causes pain as the torn fragment is torqued between the femur...
is present in over 92% of tears. It is a subjective symptom of pain in the affected knee when turning over in bed at night. Osteoarthritic pain is present with weightbearing, but the meniscal tear causes pain with a twisting motion of the knee as the meniscal fragment gets pinched, and the capsular attachment gets stretched causing the complaint of pain.
Also see: bounce home test, Thessally's test, Wilson test
Wilson test
The Wilson test is a test used to detect the presence of osteochondritis dissecans in the knee.-References:...
(internal/external rotation), and Bohler's test.
Classification of Meniscal tear
A Meniscus tear can be classified in various ways – by anatomic location, by proximity to blood supply, etc. Various tear patterns and configurations have been described. These include:• Radial tears
• Flap or Parrot-beak tears
• Peripheral, longitudinal tears
• Bucket-handle tears
• Horizontal cleavage tears
• Complex, degenerative tears
These tears can then further classified by their proximity to meniscus blood supply, namely whether they are located in the “red-red,” “red-white,” or “white-white” zones.
The functional importance of these classifications, however, is to ultimately determine whether a meniscus is REPAIRABLE. The repairability of a meniscus is dependent upon a number of factors. These include:
• Age/strength
• Activity Level
• Tear Pattern
• Chronicity of the tear
• Associated Injuries (Anterior Cruciate Ligament Injury)
• Healing Potential
Causes
There are two menisci in your knee. They sit between the thigh bone femurFemur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...
and shin bone tibia
Tibia
The tibia , shinbone, or shankbone is the larger and stronger of the two bones in the leg below the knee in vertebrates , and connects the knee with the ankle bones....
.
While the ends of the thigh bone and shin bone have a thin covering of soft hyaline cartilage, the menisci are made of fibrocartilage
Fibrocartilage
White fibrocartilage consists of a mixture of white fibrous tissue and cartilaginous tissue in various proportions. It owes its flexibility and toughness to the former of these constituents, and its elasticity to the latter...
tough cartilage and conform to the surfaces of the bones upon which they rest. One meniscus rests on the medial tibial plateau; this is the medial meniscus. The other meniscus rests on the lateral tibial plateau; this is the lateral meniscus.
These menisci act to distribute body weight across the knee joint. Without the menisci, the weight of the body would be unevenly applied to the bones in the legs (the femur and tibia). This uneven weight distribution would cause the development of abnormal excessive forces leading to early damage of the knee joint. The menisci also contribute to the stability of the joint.
The menisci are nourished by small blood vessels, but the menisci also have a large area in the center of that has no direct blood supply (avascular). This presents a problem when there is an injury to the meniscus as the avascular areas tend not to heal. Without the essential nutrients supplied by blood vessels, healing cannot take place.
The two most common causes of a meniscus tear are traumatic injury (often seen in athletes) and degenerative processes (seen in elderly patients who have more brittle cartilage). Meniscus tears can occur in all age groups. Traumatic tears are most common in active people from age 10-45. Traumatic meniscal tears are usually radial or vertical in the meniscus and are more likely to produce a moveable fragment that can catch in the knee and therefore require surgical treatment.
The most common mechanism of a traumatic meniscus tear occurs when the knee joint is bent and the knee is then twisted. It is not uncommon for the meniscus tear to occur along with injuries to the anterior cruciate ligament ACL
ACL
- Companies and organizations :* American Classical League* Arctic Co-operatives Limited* Asianet Communications Limited* Association for Computational Linguistics* Atlantic Coast Line Railroad* Atlantic Container Line* Australian Christian Lobby- Sports :...
and the medial collateral ligament MCL
MCL
- Medicine :* Mantle cell lymphoma* Mast cell leukemia* Maximum comfortable levels of auditory stimuli* Medial collateral ligament* Medical Center Leeuwarden* Medical Center of Louisiana at New Orleans* Midclavicular line* Mucocutaneous leishmaniasis...
— these three problems occurring together are known as the "unhappy triad
Unhappy triad
An unhappy triad is an injury to the anterior cruciate ligament, medial collateral ligament, and the meniscus. The triad refers to a complete or partial tear of the anterior cruciate ligament, medial collateral ligament, and the meniscus...
," which is seen in sports such as football when the player is hit on the outside of the knee. Individuals who experience a meniscus tear usually experience pain and swelling as their primary symptoms. Another common complaint is joint locking, or the inability to completely straighten the joint. This is due to a piece of the torn cartilage preventing the normal functioning of the knee joint.
Degenerative tears are most common in people from age 40 upward. Degenerative meniscal tears are thought to occur as part of the aging process when the collagen fibers within the meniscus start to break down and lend less support to the structure of the menicus. Degenerative tears are usually horizontal in the meniscus, producing both an upper and lower segment of meniscus. These segments usually don't move out of place and therefore are less likely to produce mechanical symptoms of catching or locking.
Degenerative meniscal tears are also more common in smokers.
A torn meniscus can prevent normal pain-free motion of the knee and therefore can interfere with the patient's ability to climb stairs or get in and out of chairs and cars.
Pathophysiology
The medial and lateral menisci are shock absorbers and force distributors located between the femur and the tibiaTibia
The tibia , shinbone, or shankbone is the larger and stronger of the two bones in the leg below the knee in vertebrates , and connects the knee with the ankle bones....
. Consequently, menisci can tear due to traumatic injury or degenerative wear (e.g., in knee joint arthritis
Arthritis
Arthritis is a form of joint disorder that involves inflammation of one or more joints....
), and can compromise force distribution across the knee joint, increasing force concentration on the cartilage and other joint structures.
Damage to the meniscus is due to rotational forces directed to a flexed knee (as may occur with twisting sports) is the usual underlying mechanism of injury. A valgus force applied to a flexed knee with the foot planted and the femur
Femur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...
rotated externally can result in a lateral meniscus tear. A varus force applied to the flexed knee when the foot is planted and the femur rotated internally can result in a tear of the medial meniscus.
Tears produce rough surfaces inside the knee, which cause catching, locking, buckling, pain, or a combination of these symptoms. Abnormal loading patterns and rough surfaces inside the knee, especially when coupled with return to sports, significantly increase the risk of developing arthritis if not already present.
Diagnosis
X-rayX-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
images (normally during weightbearing) can be obtained to rule out other conditions or to see if the patient also has osteoarthritis
Osteoarthritis
Osteoarthritis also known as degenerative arthritis or degenerative joint disease, is a group of mechanical abnormalities involving degradation of joints, including articular cartilage and subchondral bone. Symptoms may include joint pain, tenderness, stiffness, locking, and sometimes an effusion...
. The menisci themselves cannot be visualised with plain radiographs. If the diagnosis is not clear from the history and examination, the menisci can be imaged with magnetic resonance imaging
Magnetic resonance imaging
Magnetic resonance imaging , nuclear magnetic resonance imaging , or magnetic resonance tomography is a medical imaging technique used in radiology to visualize detailed internal structures...
(an MRI scan). This technique has replaced previous arthrography, which involved injecting contrast medium
Contrast medium
A medical contrast medium is a substance used to enhance the contrast of structures or fluids within the body in medical imaging...
into the joint space. In straightforward cases, knee arthroscopy
Arthroscopy
Arthroscopy is a minimally invasive surgical procedure in which an examination and sometimes treatment of damage of the interior of a joint is performed using an arthroscope, a type of endoscope that is inserted into the joint through a small incision...
allows quick diagnosis and simultaneous treatment. Recent clinical data shows that MRI and clinical testing are comparable in sensitivity and specificity when looking for a meniscal tear.
Conservative
The treatment course is dependent on the needs and status of the patient. A conservative course of treatment involving just physical therapy is possible. The patient will probably have to take a small break from his or her normal activities, allowing the knee to heal. Exercises can strengthen the muscles around the knee, especially the quadriceps. Stronger and bigger muscles will protect the meniscus cartilage by absorbing a part of the weight. The patient may be given paracetamolParacetamol
Paracetamol INN , or acetaminophen USAN , is a widely used over-the-counter analgesic and antipyretic . It is commonly used for the relief of headaches and other minor aches and pains and is a major ingredient in numerous cold and flu remedies...
or anti-inflammatory medications.
Surgery
If this does not resolve the symptoms or in cases of a locked knee, then surgical intervention may be required. Depending on the location of the tear, a repair may be possible. In the outer third of the meniscus, an adequate blood supply exists and a repair will likely heal. Usually younger patients are more resilient and respond well to this treatment, while older, more sedentary patients do not have a favorable outcome after a repair.The meniscus has fewer vessels and blood flow towards the unattached, thin interior edge. In the majority of cases, the tear is far away from the meniscus' blood supply, and a repair is unlikely to heal. In these cases arthroscopic surgery allows for a partial meniscectomy, removing the torn tissue and allowing the knee to function with some of the meniscus missing. In situations where the meniscus is damaged beyond repair or partial removal, a total meniscectomy is performed. This option is avoided at all costs as total meniscectomy leads to an increased risk of osteoarthritis
Osteoarthritis
Osteoarthritis also known as degenerative arthritis or degenerative joint disease, is a group of mechanical abnormalities involving degradation of joints, including articular cartilage and subchondral bone. Symptoms may include joint pain, tenderness, stiffness, locking, and sometimes an effusion...
(with loss of cartilage
Cartilage
Cartilage is a flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs...
) and eventual total knee replacement
Knee replacement
Knee replacement, or knee arthroplasty, is a surgical procedure to replace the weight-bearing surfaces of the knee joint to relieve the pain and disability of osteoarthritis. It may be performed for other knee diseases such as rheumatoid arthritis and psoriatic arthritis...
. In some cases, a meniscus replacement is done to prevent this.
Transplants of full meniscus are accomplished successfully regularly, although it is still somewhat of a rare procedure and many questions surrounding its use remain.
Post-surgical rehabilitation
After a successful surgery for treating the destroyed part of the meniscus patients must follow a rehabilitation program to have the best result. The rehabilitation following a meniscus surgery depends on whether the entire meniscus was removed or repaired.Although not clinically proven some people report better recovery after a period of oral intake of glucosamine-sulphate supplement.
If the destroyed part of the meniscus was removed, patients can usually start walking using a crutch a day or two after surgery. Although each case is different, patients return to their normal activities on average after a few weeks (2 or 3). Still, completely normal walk will resume gradually and it's not unusual to take 2–3 months for the recovery to reach a level where a patient will walk totally smoothly. Many meniscectomy patients don't ever feel a 100% functional recovery, but even years after the procedure they sometimes feel tugging or tension in a part of their knee. There is little medical follow-up after meniscectomy and official medical documentation tends to ignore the imperfections and side-effects of this procedure.
If the meniscus was repaired the rehabilitation
Physical therapy
Physical therapy , often abbreviated PT, is a health care profession. Physical therapy is concerned with identifying and maximizing quality of life and movement potential within the spheres of promotion, prevention, diagnosis, treatment/intervention,and rehabilitation...
program that follows is a lot more intensive. After the surgery a hinged knee brace is sometimes placed on the patient. This brace allows controlled movement of the knee. The patient is encouraged to walk using crutches from the first day, and most of the times can put partial weight on the knee.
The time course varies with each patient. Starting from the second month the patient maybe able to walk freely and can also do various "low-impact" exercises (static bicycle, swimming, etc.), but should expect the knee to feel stiff and sore. If the rehabilitation was done properly the patient can gradually return back to "high-impact" activities (like running). However, "heavier activities", like running, skiing, basketball etc., generally any activities where knees bear sudden changes of the direction of movement can lead to repeated injuries. When planning sport activities it makes sense to consult a physical therapist and check how much impact the sport will have on the knee.